The purpose of this study is to prevent diabetes from developing in obese African American children. Obesity often leads to high blood sugar and diabetes. Diabetes causes heart disease, damage to the eyes and stroke. Children who are overweight may be more likely to develop diabetes as they grow older. The purpose of this study is to identify obese children who are at high risk for becoming diabetic and control their weight gain in order to prevent development of diabetes as they get older. We will also study which type of program is best at controlling weight gain in children. This study will be conducted in two parts. Part I will identify obese children who do not have diabetes, have at least average learning ability and are interested in participating in a weight control program. In Part II there will be random assignment to 1 of 3 concurrently conducted weight control programs. Participation in these specific weight control programs will last for 3 years. At close out metabolic and psychologic studies will be repeated.